Patent GB-644918-A (GB)
Title: Manufacture of protein hydrolysates
IPC: A23J3/34
Filed: 1947-07-25
Abstract: Protein hydrolysates for therapeutic purposes are obtained by subjecting edible protein to pancreatic digestion, or pancreatic digestion followed by ereptic digestion in an aqueous medium maintained at pH 7-10 by means of an alkaline earth compound of alkaline reaction, and treating the resulting hydrolysate to bring the amino acids into solution and remove the whole or most of the alkaline earth metal radical.  The preferred alkaline earth metal compounds are barium oxide or hydroxide or calcium oxide or hydroxide.  The amino acids are solubilized and the alkaline earth metals are removed by acidifying the hydrolysate, preferably to pH 4.6-5.0, with an acid forming an insoluble salt with the alkaline earth metal, heating the mixture and separating the insoluble material from the liquid.  Sulphuric acid may be used in the case of barium and phosphoric acid in the case of calcium.  According to an example, minced beef pancreas, chloroform and toluene are added to a suspension of casein powder and calcium hydroxide in water and digestion is effected for several days at 37-40 DEG  C. When the digestion is complete, minced small intestines of beef are added and digestion is effected for several days at 37-40 DEG  C. The liquid is screened to separate fat, heated to boiling and mixed with sufficient phosphoric acid to bring the pH to 4.6-5.0. The liquid is filtered and the filtrate is evaporated under reduced pressure to a paste. The paste may be mixed with syrup, glycerine, alcohol or flavouring agents.  In a second example, calcium hydroxide is replaced by barium hydroxide, and phosphoric acid by sulphuric acid.  The Specification as open to inspection under Sect. 91 comprises also the employment of ammonium hydroxide instead of the alkaline earth metal compound, the hydrolysate being concentrated under reduced pressure to remove part of the ammonia, the concentrate after dilution being acidified to pH 4.6-5.0 by the addition of glacial acetic acid and the acidified liquid being further concentrated.  This subject-matter does not appear in the Specification as accepted.ALSO:Protein hydrolysates for therapeutic purposes are obtained by subjecting edible protein to pancreatic digestion, or pancreatic digestion followed by ereptic digestion in an aqueous medium maintained at pH 7-10 by means of an alkaline earth compound of alkaline reaction, and treating the resulting hydrolysate to bring the amino acids into solution and remove the whole or most of the alkaline earth metal radical.  The preferred alkaline earth metal compounds are barium oxide or hydroxide or calcium oxide or hydroxide.  The amino acids are solubilized and the alkaline earth metals are removed by acidifying the hydrolysate, preferably to pH 4.6-5.0, with an acid forming an insoluble salt with the alkaline earth metal, heating the mixture and separating the insoluble material from the liquid.  Sulphuric acid may be used in the case of barium, and phosphoric acid in the case of calcium.  According to an example, minced beef pancreas, chloroform and toluene are added to a suspension of casein powder and calcium hydroxide in water and digestion is effected for several days at 37 DEG -40 DEG C. When the digestion is complete, minced small intestines of beef are added and digestion is effected for several days at 37 DEG -40 DEG C. The liquid is screened to separate fat, heated to boiling and mixed with sufficient phosphoric acid to bring the pH to 4.6-5.0. The liquid is filtered and the filtrate is evaporated under reduced pressure to a paste.  The paste may be mixed with syrup, glycerine, alcohol or flavouring agents.  In a second example, calcium hydroxide is replaced by barium hydroxide, and phosphoric acid by sulphuric acid.  The Specification as open to inspection under Sect. 91 comprises also the employment of ammonium hydroxide instead of the alkaline earth metal compound, the hydrolysate being concentrated under reduced pressure to remove part of the ammonia, the concentrate after dilution being acidified to pH 4.6-5.0 by the addition of glacial acetic acid and the acidified liquid being further concentrated.  This subject-matter does not appear in the Specification as accepted.